The technique proposed in this study uses a transmission detector, similar in function to the
monitor chambers of a linac, as the scanning reference chamber. Evaluated in this study is the Stealth
Detector (IBA Dosimetry), a transmission detector which perturbs the primary beam minimally, evenly,
and consistently. The use of this detector would give rise to a time savings associated the user not having
to perform a readjustment of the reference detector prior to each field-size change. The purpose of this
study is threefold. First, it is important to determining the extent by which the beam is perturbed along the
central axis by the inclusion of this transmission detector. Next, is the determination of the effect on the
energy spectra of the field by evaluating percent depth dose scans using the transmission detector and
comparing those to scans using standard reference detectors. Finally, profile scans using both types of
reference detectors are compared.